1. Field of the Invention
The present invention relates to quick erect shelters, and more particularly to frames including hubs and hub assemblies for quick erect shelters.
2. Description of the Related Art
A quick erect shelter, such as shown in FIG. 1, is a completely integrated, modular shelter system, which is rugged and flexible in design. The quick erect shelter 20 is designed for rapid setup as well as rapid breakdown. The shelter 20 includes an exterior canopy 22 and an interior liner 24 that are preattached to an articulate frame 26 which expands to an arched frame when erected. The shelter 20 is self-supporting, which eliminates the need for supplementary erection devices, such as push poles, and supplementary support devices, such as center poles.
The self-supporting nature of the shelter 20 is derived from its articulate frame 26. As shown in FIGS. 2(a) and (b), the articulate frame 26 consists of cylindrical aluminum tubes, referred to as struts 28, which are interconnected to hubs 30 by pivotal joints 32. Each hub 30, which may interconnect with as many as four struts 28, includes a hole 36 which enables the exterior canopy 22 and interior liner 24 to be attached to each hub 30, depending upon whether the hub 30 is located on the external or internal portion of the articulate frame 26, respectively. The hole 36 also enables a stabilizing rod 34 to be partially inserted into the hub 30 in order to provide additional support to the frame 26 and to maintain the symmetry of the frame 26. The stabilizing rod 34 consists of a solid aluminum cylindrical rod. The rod 34 is connected at a threaded end to the hole 36 of one hub 30, and is forcibly wedged at its opposing end into the hole 36 of an opposing hub 30.
A typical quick erect shelter is arranged such that the plurality of struts 28 and hubs 30 form a lattice framework. In the expanded configuration, as shown in FIGS. 1 and 2(a), the struts 28 are assembled to form an arch as the basic building block of each shelter 20. Shelters 20 can be manufactured to any desired length by connecting arched sections with additional struts 28.
Heretofore, quick erect shelters used a conventional hub as shown in FIGS. 3(a)-3(c). A conventional hub 30 consists generally of a two-piece assembly made up of a base 38 and a body 40. The base 38 is square-shaped, has a uniform thickness, and has a hole 36 extending through its center portion. The base 38 further includes an upper surface 42 and a bottom surface 44. The body 40, which is attached via screws to the upper surface 42 of the base 38, consists of a rectangular center portion 46 communicating with ends of arms 48 extended at right angles all in the same rotary direction, thus, forming rectangular cutout portions 45. In short, the body 40 is formed in the shape of a swastika of uniform thickness.
The rectangular center portion 46 has a hole 50, extending therethrough, which is axially aligned with the hole 36 of the base 38. A mounting means 52, e.g., a nut 51 and a bolt 52 (or alternatively, a bolt and a threaded insert, or other comparable connecting means), may be fed through the exterior canopy 22 or interior liner 24 of the shelter 20 (depending upon where the hub 30 is located) through the hole 36 of the base 38 and through the hole 50 of the center portion 46 in order to connect the hub 30 to the exterior canopy 22 or interior liner 24.
Each arm 48 of the body 40 includes a rectangular first portion 54 having a hole 58 extending therethrough in a direction perpendicular to a face 49 of the first portion 54. Each arm 48 further includes a rectangular second portion 56 having a bore 60 extending into a side thereof in a direction perpendicular to the hole 58 of the first portion 54. The bore 60 of the second portion 56 of each arm 48 is axially aligned with the hole 58 of the first portion 54 of an adjacent arm 48.
A strut 28 is pivotally connected between two adjacent arms 48 of the hub 30 by a pin 62. The pin 62 extends through the hole 58 of the first portion 54 of an arm 48, through an end portion of the strut 28 and into the bore 60 of the second portion 56 of an adjacent arm 48.
The typical shelter framework, hubs, and hub assemblies heretofore described are satisfactory for the purposes intended. However, for certain applications it is desirable to provide a quick erect shelter that has the strength and advantages of typical shelters but which are lighter in weight, easy to assemble, and whose frame is capable of including utility lines such as electric, gas, and water.